Proving that the totient function increases infinitely

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In summary, the task is to prove that as n approaches infinity, the totient function (\varphi(n)) also approaches infinity. The approach suggested is to show that \varphi(n) is always greater than some increasing estimate of itself. One possible method is to consider the integer k with the maximum value of the totient function, and show that by multiplying it with a larger prime number, the resulting value of the totient function will also increase. This implies that there can never be an integer with the maximum value of the totient function, and therefore as n increases, the totient function also increases. More clarification on the meaning of "increasing estimate of itself" and alternative approaches for the proof are welcome.
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Homework Statement


Prove that [itex]\varphi[/itex](n)→∞ as n→∞. n[itex]\in[/itex]Z


Homework Equations


[itex]\varphi[/itex](n) = the number of integers less than n that are coprime to n.


The Attempt at a Solution


My professor said that we need to show that [itex]\varphi[/itex](n) is always greater than some increasing estimate of itself. I'm really not sure how to even go about applying this. Any help you could offer would be really appreciated.

What I was thinking of doing would be to say let k be the integer with the maximum value of the totient function. k=p1[itex]\alpha[/itex]1...pn[itex]\alpha[/itex]n where pi is a prime number. So [itex]\varphi[/itex](k) = [itex]\varphi[/itex](p1[itex]\alpha[/itex]1...pn[itex]\alpha[/itex]n)=[itex]\varphi[/itex](p1[itex]\alpha[/itex]1)...[itex]\varphi[/itex](pn[itex]\alpha[/itex]n). Multiply k by any prime greater than pn, called pl. Call this number j. Then [itex]\varphi[/itex](j)=[itex]\varphi[/itex](p1[itex]\alpha[/itex]1)...[itex]\varphi[/itex](pn[itex]\alpha[/itex]n)[itex]\varphi[/itex](pl[itex]\alpha[/itex]l). This new multiple is greater than zero (I would write out the basis case in order to guarantee this), so the second equation is greater than the first, so there cannot be an integer with the maximum value of the totient. In other words, as n increases, the totient function increases.
 
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I'm not sure if this is really what my professor meant by "show that \varphi(n) is always greater than some increasing estimate of itself." If anyone could provide insight into what this means and how I should go about proving it, I would really appreciate it.
 

FAQ: Proving that the totient function increases infinitely

What is the totient function?

The totient function, also known as Euler's totient function, is a mathematical function that counts the number of positive integers less than or equal to a given number that are relatively prime to that number.

How is the totient function related to prime numbers?

The totient function is closely related to prime numbers because it is defined as the number of positive integers that are relatively prime to a given number. This means that the totient function can only take on certain values for prime numbers.

Why is it important to prove that the totient function increases infinitely?

Proving that the totient function increases infinitely is important because it helps us understand the distribution of prime numbers and their properties. It also has applications in number theory, cryptography, and other areas of mathematics.

How can we prove that the totient function increases infinitely?

There are several ways to prove that the totient function increases infinitely. One approach is to use the prime number theorem, which states that the number of primes less than or equal to a given number is approximately equal to that number divided by the natural logarithm of that number. Another approach is to use the Euler product formula, which relates the totient function to the product of primes.

What implications does the proof of the totient function have on other mathematical concepts?

The proof of the totient function has implications on various other mathematical concepts, such as the distribution of primes, the Riemann hypothesis, and the Goldbach conjecture. It also has applications in algorithms for finding prime numbers and in the study of group theory.

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